Myriopholis wilsoni (HAHN, 1978)
Can you confirm these amateur observations of Myriopholis wilsoni?
|Higher Taxa||Leptotyphlopidae, Leptotyphlopinae, Myriopholini, Typhlopoidea, Serpentes, Squamata (snakes)|
|Common Names||E: Wilson's Blind Snake|
|Synonym||Leptotyphlops wilsoni HAHN 1978|
Leptotyphlops wilsoni — MCDIARMID, CAMPBELL & TOURÉ 1999: 46
Leptotyphlops cf. wilsoni — RÖSLER & WRANIK 2004
Myriopholis wilsoni — ADALSTEINSSON, BRANCH, TRAPE, VITT & HEDGES 2009
Myriopholis wilsoni — WALLACH et al. 2014: 466
|Distribution||Socotra Island (Yemen).|
Type locality: Kirschon, Socotra Island.
|Types||Holotype: BMNH 19220.127.116.11|
|Diagnosis||Original diagnosis: “Leptotyphlops wilsoni belongs to the most generalized group of the Old World Leptotyphlops, characterized by having a rounded snout, a prefrontal, and 10 scale rows around the middle of the tail. Besides L. wilsoni, the longicaudus-group contains cairi, boulengeri, longicaudus, narirostris, nigricans, and reticulatus, all African forms.” (Hahn 1978)|
Diagnosis: Leptotyphlops wilsoni was described on the basis of two specimens by Hahn (1978) (see also Corkill and Chochrane 1966). L. wilsoni differs from L. filiformis and L. macrurus by a short, rounded, not hooked snout and a proportional smaller rostral; from L. filiformis it differs additionally in a lower number of dorsals. According to Hahn (1978) the occipitals in L. wilsoni are undivided, but divided in L. filiformis and L. macrurus, which was not confirmed by Schätti and Desvoignes (1999) [from RÖSLER & WRANIK 2006].
Description of the holotype: “Total length 100mm; mid-body horizontal diameter 1.5 mm; diameter into total length 66.7 times.
Head slightly wider than neck; snout rounded in lateral view, with no concavity to preoral portion of rostral; rostral short, not reaching the level of the eye posteriorly; rostral approximately one-half the width of the head at its widest point; nasal completely divided; upper nasal approximately equal in width to the ocular; small, single anterior supralabial between ocular and lower portion of nasal; supraoculars present, about equal in size to frontal and prefrontal; ocular reaches lip; eyes visible; cutaneous touch corpuscles (=head scale tubercules) numerous on rostral, nasals, and oculars; posterior supralabial large, reaching eye level dorsally; interparietal slightly larger than frontal and prefrontal; parietals and occipitals undivided; mental not present; six infralabials.
Total dorsals number 287; 14 scale rows around body; 10 scale rows around the middle of tail; tail length 19 mm, coming to an acute point after a long, even taper; tail length into total length 5.3 times; tail length 12.7 times tail diameter; subcaudals number 49.
Diffuse olive green to brown pigmentation on 9 dorsal-most scale rows at mid-body, pigment extends completely around the tail; ventral body pigmentation light brown, with no clear-cut line of demarcation from dorsal pigmentation; dorsal pigmentation heaviest on anterior edges of scales.” (Hahn 1978)
Comparisons: Leptotyphlops cairi (Dumeril and Bibron) from northeast Africa attains a much greater length and diameter than does wilsoni, differs in having divided occipitals, fewer subcaudals (28-36), and the rostral reaches the level of the eye.
L. reticulatus (Boulenger) from Somalia is distinguished from wilsoni by having fewer total dorsals (227-238), fewer subcaudals (29-32), an anterior supralabial equal to, or larger than, the inferior portion of the nasal. Furthermore, reticulatus is a much larger species (up to 200 mm), and has a distinct black and light reticularcolor pattern.
L. nigricans (Schlegel) has fewer subcaudals (19-33) than wilsoni, the supraoculars are distinctly largerthan the prefrontal,the rostral reaches the level of the eyes posteriorly, and it is uniformly dark pigmented (Broadley and Watson, 1976). Its range is discontinuous from South Africa to southern Sudan. After comparing several Zaire specimens of L. emini with South African L. nigricans, I agree with Broadley and Watson(1976) that they are conspecific.
Leptotyphlops boulengeri (Boettger) from Manda Island, Kenya is remarkable in its stoutness of form, the total length being only 29.9 times the midbody horizontal diameter; L. wilsoni, by comparison, ranges from 50.5 to 66.7 times. In addition,boulengeri has far fewer total dorsals (192), subcaudals(18), and a much shorter tail, tail length/total length ratio, 10.3.
Leptotyphlops narirostris (Peters) from West Africa is most closely related to L. reticulatus.This is a much larger species than wilsoni, the longest specimen examined measuring 191 mm in total length. It also differs in having a long tail which is stout its entire length, tapering abruptly close to its terminus; the first supralabial is larger than the infranasal; and it has a slightly stouter body form, the midbody diameter going into the total length 38.3 to 47.3 times. [...]
If the original description of L. natatrix (Andersson) is accurate, this species has two characteristics not found in any other species of Leptotyphlops: a distinctly flattened, oar-like tail, and two supralabials posterior to the ocular. The holotype is from the Tobo Swamp, Gambia, and is in the Naturhistoriska Rijksmuseum,Stockholm.
Leptotyphlops wilsoni differs from the other Socotran species, L. macrurus and filiformis, in having a rounded snout and undivided occipitals. In addition, wilsoni also has far fewer total dorsals (287-300) than does filiformis (479-487). Both macrurus and filiformis belong to the macrorhynchus-group.
The two Asian round-snouted Leptotyphlops species, buri and blanfordi, are also in a more advanced species group than is wilsoni. In addition to having 12 scale rows around the tail, L. buri (Boulenger) also differs from wilsoni by having more total dorsals (403-408), fewer subcaudals (28-33), divided occipitals, the rostral reaching posteriorly to the level of the eye, and is a much larger species, reaching at least 205 mm in total length.
Leptotyphlops blanfordi (Boulenger) differs from wilsoni by having 12 scale rows around the tail, and a proportionately shorter tail, the tail length going into the total length 10.0 to 16.8 times.” (Hahn 1978)
|Comment||Distribution: For a map see Sindaco et al. 2013.|
Known only from the holotype.
|Etymology||Named after Dr. Larry David Wilson (b. 1940), American herpetologist formerly at the Department of Biology, Miami-Dade Community College, Florida.|
Note that Beolens et al. (2011) erroneously claimed that the species was named after Dr. Don Ellis Wilson (b. 1944), a zoologist who graduated from the University of Arizona (1955).